Apparatus for advancing strip material



Aug. 12, 1947. c. B. LL-JBBIERT ,3

APPARATUS FOR ADVANCING STRIP MATERIAL Filed April 26, 1945 2 Sheets-Sheet 2 l/ENTOR C'. LUBBERT ATTOELNEK 1 fatentecl Aug. 12, 194

UNITED STATES PATENT OFFICE APPARATUS FOR ADVANCIN G STRIP MATERIAL Carl B. Lubbert, Anneslie, Md., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application April 26, 1945, Serial No. 590,377

8 Claims. (Cl. 164-416) This invention relates to apparatus for advancing strip material and has for its object the provision of new and improved apparatus for advancing strip material.

In punching articles from strips of plastic material, such as polyethylene, the strips should not be stretched or the articles punched therefrom will not have uniform dimensions. One type of apparatus for punching articles from such strips includes a punch press, means for pushing strips of material toward the punch press and means for pulling the strips of material away from the punch press. It is desirable to operate the pushing means and the pulling means at separate times to prevent buckling or stretching of the strips.

An apparatus forming one embodiment of the invention comprises means for pushing a strip of material toward a punch press, means for pulling the strip of material away from the punch press and means for disengaging the pushing means from the strip when the pulling means becomes operative.

A complete understanding of the invention may be obtained from the following detailed description of an apparatus forming a specific embodiment thereof, when read in conjunction with the appended drawings, in which Fig. 1 is a horizontal section of an apparatus forming one embodiment of the invention;

Fig. 2 is a front elevation thereof;

Fig. 3 is an enlarged vertical section taken along line 3-3 of Fig. 1;

Fig. 4 is an enlarged, vertical section taken along line 44 of Fig. l, and

Fig. 5 is an enlarged, vertical section taken along line 5-5 of Fig. 1.

Referring now in detail to the drawings, a punch press l (Figs. 1 and 2) includes a reciprocable punch II and a stationary die l2. The reciprocable punch is reciprocated toward and away from the stationary die |2 by a ram I3, which is reciprocated by suitable reciprocating means (not shown) and the punch and the die serve to punch parts from a strip I made of plastic material, such as polyethylene. The strip may be pushed toward the punch press H) by pushing rolls l6 and I! and may be pulled away from the punch press by pulling rolls 20 and 2|.

A rod 22 is reciprocated by the reciprocating means in synchronization with the reciprocation of the punch H and drives a ratchet mechanism 25, which rotates intermittently the pulling rolls 2D and 2| in opposite directions through gears 26 and 27. The ratchet mechanism 25 drives the pulling rolls only when the punch H is moved out of engagement with the strip IS. A connecting rod 30 connects the ratchet mechanism 25 with a ratchet mechanism 3|, which drives intermittently the pushing rolls I6 and I1 through gears 32 and 33. The pushing rolls and the pulling rolls are driven only when the punch is out of engagement with the strip.

The pushing roll I6 is rotatably mounted in bearings 36-36 (Figs. 2 and 4), which are mounted slidably in guideways 34--34 formed in standards 38-38 and are urged by compression springs 3'|31 downwardly, as viewed in Figs. 2 and 4, whereby the pushing roll 5 is urged toward the strip |5 and the pushing roll H. A bar 39 (Figs. 2 and 4) connecting levers 40-40 when engaged by a lobe 4| of a cam 42 holds the levers in positions in which they hold the bearings 36-36 in an elevated position so that the pushing roll I6 is held out of operative engagement with the strip, whereby the strip is not pushed by the pushing rolls. The cam 42 is mounted upon a shaft 43 and has a depression 44 formed thereon. When the depression 44 is in engagement with the bar 39, the compression springs 3'|--3'l move bearings 36-36 downwardly, as viewed in Fig. 2, whereby the pushing roll I6 is moved into operative engagement with the strip so that it is advanced toward the punch press H] by the pushing rolls.

When a handwheel 45 (Figs. 1 and 2) secured to the shaft 43 is rotated in a clockwise direction, as viewed in Fig. 2, the shaft 43 is rotated and a torsion spring 46, whose ends are secured to the cam 42 and a bearing 50, is wound up and the lobe 4| of the cam 42 is moved out of engage- I ment with the bar 39, whereby the pushing roll I6 is pressed against the strip l5. When the shaft 43 is so rotated, a cam secured thereto is rotated to the position shown in dotted lines in Fig. 5, at which time a shoulder 56 formed on the cam 55 is engaged by a catch 51 formed on a. lever 60, whereby the shaft 43 is held against counter clockwise movement, and the pushing roll I6 is held in operative engagement with the strip.

The lever 63 is urged by a tension spring 6| in a counterclockwise direction, as viewed in Fig. 5, and the counterclockwise movement of the lever is limited by an adjustable stop 62. The lever 60 is connected by a link 65 to an armature 65 of a solenoid 61. When a winding 68 of the solenoid 67 is energized, the armature is drawn downwardly, whereby the catch 57 is drawn out torsion spring 46 (Fig. 1) rotates the shaft 43 shaft 43 is limited by a stop 59 (Fig. 1) which engages a dog Ill fastened to the shaft 43 so that the lobe 4| formed on the cam 52 is held in 'en-.

gagement with the bar 39.

A pair of compression springs l|l| (Figs. 2 and 3) urge bearings '|2-'|2 downwardly, as viewed in Fig. 2, in guideways 18-18 formed in standards 19-49, whereby the pulling roll 20,

. which is rotatably mounted in the bearings 12- i2, is urged toward the strip l5 and the pulling roll 2|. Levers 13-13 connected by a bar 14 serve to lock the bearings |2|2 against the j actions of the springs ll-1| when engaged by a lobe 15 formed on a cam l6, whereby the pulling roll is held out of operative engagement with respect to the strip. The cam 16 is provided with a depression 11 and when the depression i1 is moved into contact with the bar M, the compression springs ll-H urge the pulling roll into operative engagement with the strip. The cam 76 is rigidly fastened to a shaft 8| and an operating handle 8| also is secured thereto. When the handle is in its upper position, as viewed in Fig. 3, the lobe 15 of the cam 16 engages the bar 14. When the handle is moved from its upper position to its lower position, the depression TI is moved into engagement with the bar 14 and the pulling roll 20 is moved by the compression springs into operative relationship with respect to the strip, whereby the rolls 2!) and 2| pull the strip through the press Hi.

When the handle 8| is moved from its upper position to its lower position so that the pulling roll 20 moves into operative relationship with respect to the strip |5, an arm 82 mounted rigidly on the shaft 8|] engages an actuatingarm 85 of a microswitch 85 and closes the contacts (not shown) of the microswitch. The contacts of the microswitch are in series with the winding 68 (Fig. 5) of the solenoid 61, and when they are closed, the winding 68 is energized and the armature 66 thereof is drawn downwardly, as viewed in Fig. 5. This draws the catch 5'! formed on the lever 60 away from the shoulder 56 of the cam 55, which permits the torsion spring 45 (Fig. 1) to rotate the shaft 43, whereby the pushing roll i5 is moved out of operative relationship with i the strip so that the pushing rolls H5 and I1 cease pushing the strip at the same time that the pulling rolls 2|] and 2| start pulling the strip.

In the operation of the apparatus described hereinabove, when both the set of pushing rolls l6 and I1 and the set of pulling rolls 2% and 2| are out of feeding relationship and the punch H is reciprocated intermittently with respect to the die l2, the strip I5 is slid manually between the pushing rolls I5 and I7 toward the punch press HI until the left end thereof, as viewed in Fig. 2, approaches the punch press In. The handwheel 45 then is rotated in a clockwise direction, as viewed in Fig. 2, and the shoulder 56 of the cam 55 (Fig. 5) is caught by the catch 51, whereby the pushing roll |6 (Fig. 4) is moved into and is held in operative relationship with respect to the strip. The pushing rolls then serve to inter mittently advance the strip through the press.

When the left end of the strip l5, as viewed in Fig. 2, has been advanced to a position between the pulling rolls 2%} and 2|, which are out of operative engagement therewith at this time, the handle 8| is moved in a counterclockwise direction, as viewed in Fig. 2. This causes the pulling roll 20 to be moved into feeding relationship with respect to the strip and the arm 82 (Fig. '3) simultaneously strikes the actuating arm 85, which closes the contacts of themicroswitch 8B. When the contacts of the microswitch Stare closed, the

,winding 68 (Fig. 5) of the solenoid 5'! is energized, whereby the armature '66 moves the catch 51 of the lever 69 out of engagement withrthe shoulder 55 formed on the cam 55. This permits.

the torsion spring 45 (Fig. 1) to move the pushing roll |6 out of operative relationship with the strip so that only the pulling rolls 2|) and 2| advance the strip.

The press ll) continues to operate without any interruption and the strip I5 is pulled completely through the press by the pulling rolls 20 and 2|. After the strip l5 has been advanced completely beyond the punch press lflythe handle Elvis actuated so that the pulling roll 20 is moved out of operative relationship with respect to the strip, which is withdrawn therefrom. Another strip, similar to the strip, 15 then is inserted between the pushing rolls i6 and H, the 'handwheel 45 is actuated to permit the, pushing roll It to be moved into the feeding relationship with respect to the pushing roll H, and the operation described hereinabove is repeated. 7

"The pushing roll I5 is movedautomatically out of operative relationship with respect to the strip l5 at the instant the pulling roll 20 is moved into operative relationship with respect to the strip so that no interruption in the advancement of the strip occurs. However, there is no overlapping of the periods of feeding of the pushing rolls and the pulling rolls so that no buckling or stretching of the strip is caused by possible changes in the feeding rates'of the two sets of rolls. Thus, the uniformity of the articles punched from the strip is not affected adversely; as is possible where the periods of feeding of the two sets of rolls overlap.

What is claimed is: r j

1. Apparatus for feeding material to a Punch press, which comprises means for 1 pushing a strip of material toward the punch press, means for pulling the strip of material away from'the punch press, and means for disengaging the pushing means from the strip when the pulling means becomes operative.

2. Apparatus for feeding material to a punch press, which comprises means for pushing a strip of material toward the punch press, means for pulling the strip away from the punch press, means for actuating the pushing means to stop, the pushing operation thereof, and means for starting the pulling operation of the pulling means and for operating the actuating means simultaneously therewith.

3. Apparatus for feeding material 'to a'punch press, which comprises a set of pushing rolls for pushing a strip of material toward the punch press, a set of pulling rolls for pulling from the strip away from the punch press, and means for disengaging the set of'pushing rolls from the strip when the set 'of pulling rolls become operative. V r

4. Apparatus for feeding materialto a punch press, which comprises a set of pushing rolls for pushing a strip of material toward the punch press, a set of pulling rolls for pullingfrom the punch press a strip of material pushed by the set.

pushing rolls into operative relationship with respect to a strip of material, means for moving the set of pushing rolls out of operative relationship with respect to a strip of material pushed thereby, means for moving the pulling rolls into operative relationship with respect to the strip, and means actuated by the last-mentioned means for actuating the means for moving the pushing rolls out of operative relationship with respect to the strip.

5. Apparatus for feeding material to a punch press, which comprises a set of pushing rolls for pushing a, strip of material toward the punch press, a set of pulling rolls for pulling from the punch press a strip of material pushed by the set of pushing rolls, means for latching the set of pushing rolls in operative relationship with respect to the strip, means for moving the set of pulling rolls into operative relationship with respect to the strip, and means actuatable by the last-mentioned means for releasing the latching means.

6. Apparatus for feeding material to a punch press, which comprises a set of pushing rolls for advancing a strip of material to the punch press, a set of pulling rolls for advancing from the punch press a strip of material advanced by the set of pushing rolls, means for moving the set of pushing rolls into operative relationship with respect to the strip, means for urging the set of pushing rolls out of operative relationship with respect to the strip, means for latching the set of pushing rolls in operative relationship with respect to the strip, means for moving the set of pulling rolls out of operative relationship with respect to the strip, means for moving the set of pulling rolls into operative relationship with respect to the strip, and means operable by the lastmentioned means for releasing the latching means so that the set of pushing rolls is moved out of operative relationship with respect to the strip as the set of pulling rolls is moved into operative relationship therewith.

'7. Apparatus for feeding material to a punch press, which comprises a set of pushing rolls for advancing a strip of material toward the punch press, a set of pulling rolls for advancing from the punch press a strip of material advanced by the set of pushing rolls, means for urging the set of pushing rolls out of operative relationship with respect to the strip, means for latching the set of pushing rolls in operative relationship with respect to the strip, means for holding the set of pulling rolls out of operative relationship with respect to the strip, means for urging the set of pulling rolls into operative relationship with respect to the strip, means for releasing the last-mentioned holding means, and means operable by the releasing means for releasing the latching means, whereby the pushing rolls are moved out of operative relationship with respect to the strip.

8. Apparatus for feeding material to a punch press, which comprises a set of pushing rolls movable into and out of operative relationship with a strip of material for advancing it toward the punch press when moved into operative relationship therewith, a set of pulling rolls movable into and out of operative relationship with the strip for advancing it from the punch press when moved into operative relationship therewith, means for urging the set of pushing rolls out of operative relationship with respect to the strip, means for moving the pushing rolls into operative relationship with respect to the strip, means for latching the set of pushing rolls in operative relationship with respect to the strip, means for moving the set of pulling rolls into operative relationship with respect to the strip, a solenoid having a winding for releasing the latching means when energized, a switch having normally open contacts in series with the winding of the solenoid, and means'associated with the last-mentioned moving means for closing the contacts of the switch when the set of pulling rolls is moved into operative relationship with the strip, whereby the set of pushing rolls is moved out of operative relationship with the strip at the sam time that the set of pulling rolls is moved into operative relationship therewith.

CARL B. LUBBERT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

